Last time we got a good look at Christina Aguilera in July, she appeared pretty and fit. But her slimmed-down style on last night's (Sept. 18) 'Tonight Show With Jay Leno' was simply stunning!

Xtina rocked a truly little LBD and a wide smile for her chat with the late-night host. She was there to promote her return to the panel of 'The Voice' for its upcoming fifth season -- but all Leno seemingly wanted to talk about was her upcoming spread in Maxim.

He asked Aguilera, who covers the men's magazine's October issue, about her quote in the accompanying article saying, "I've never been one to shy away from my sexuality."

The singer explained herself: "I'm an artist, and expressing myself in a sexual way, no matter how that changes throughout the years, has always been something that has always come naturally to me. At this point of my life, I'm 32 and I feel sexier than ever just because you know what you want. So it was all about -- the shoot, yes, I was in control of that -- but it was all just about appreciating the woman I've become, and effortless sexy, not trying too hard."

Speaking of not trying too hard, the diva says she hardly works out, which might be the most amazing thing about her amazing figure!